When will the deferred function defer be called? When exiting the local block, when exiting the function, or when the application terminates?.

In C#, the keyword defer does not exist, but if we talk about the defer construct from other languages (for example, Go), then the deferred function is called upon exiting the current function in which it is declared.

That is, defer triggers at the end of the function, not when exiting a local block or when the entire application terminates.

If we talk about C#, then similarly, you can use a finally block to execute code upon exiting a method.